Life Processes and Nutrition

Definition of Life Process

• A series of activities performed by living organisms to maintain their existence and ensure survival
• Essential functions necessary for an organism to grow, respond to stimuli, reproduce, and maintain homeostasis

Basic Life Processes

1. Nutrition

• Ingestion: taking in food and nutrients
• Digestion: breaking down complex molecules into simpler ones
• Absorption: absorption of nutrients into the bloodstream
• Assimilation: using absorbed nutrients for energy and growth

2. Respiration

• Breathing in oxygen (O2)
• Releasing energy from glucose (cellular respiration)
• Breathing out carbon dioxide (CO2)

3. Transportation

• Movement of substances within the body
• Circulatory system: heart, blood vessels, and blood
• Transportation of oxygen, nutrients, and waste products

4. Excretion

• Removal of waste products from the body
• Kidneys: filter waste and excess substances from blood
• Liver: detoxifies harmful substances
• Skin, lungs, and kidneys: eliminate waste products

5. Regulation and Control

• Nervous system: receives and responds to stimuli
• Endocrine system: produces hormones to regulate various functions
• Homeostasis: maintaining a stable internal environment

6. Growth and Development

• Increase in size and complexity
• Differentiation: formation of specialized cells and tissues
• Morphogenesis: formation of body shape and structure

7. Reproduction

• Production of offspring
• Sexual reproduction: fusion of gametes (sperm and egg cells)
• Asexual reproduction: production of offspring without gametes

8. Response to Stimuli

• Ability to detect and respond to changes in the environment
• Sensory organs: detect light, sound, touch, taste, and smell
• Motor responses: muscle contractions and relaxations

Life Processes

• Life processes are a series of activities performed by living organisms to maintain their existence and ensure survival.
• Essential functions necessary for an organism to grow, respond to stimuli, reproduce, and maintain homeostasis.

Nutrition

• Ingestion involves taking in food and nutrients.
• Digestion breaks down complex molecules into simpler ones through mechanical and chemical means.
• Absorption involves the absorption of nutrients into the bloodstream through the walls of the digestive system.
• Assimilation uses absorbed nutrients for energy and growth.

Respiration

• Breathing in oxygen (O2) is necessary for cellular respiration.
• Cellular respiration releases energy from glucose.
• Breathing out carbon dioxide (CO2) is a byproduct of cellular respiration.

Transportation

• The circulatory system, comprising heart, blood vessels, and blood, enables the movement of substances within the body.
• Oxygen, nutrients, and waste products are transported throughout the body.

Excretion

• Excretion involves the removal of waste products from the body.
• Kidneys filter waste and excess substances from blood.
• The liver detoxifies harmful substances.
• Skin, lungs, and kidneys eliminate waste products.

Regulation and Control

• The nervous system receives and responds to stimuli.
• The endocrine system produces hormones to regulate various functions.
• Homeostasis maintains a stable internal environment.

Growth and Development

• Growth involves an increase in size and complexity.
• Differentiation involves the formation of specialized cells and tissues.
• Morphogenesis involves the formation of body shape and structure.

Reproduction

• Reproduction involves the production of offspring.
• Sexual reproduction involves the fusion of gametes (sperm and egg cells).
• Asexual reproduction involves the production of offspring without gametes.

Response to Stimuli

• Response to stimuli involves the ability to detect and respond to changes in the environment.
• Sensory organs detect light, sound, touch, taste, and smell.
• Motor responses involve muscle contractions and relaxations.

Life Processes

Photosynthesis

• Converts light energy into chemical energy in plants, algae, and some bacteria
• Equation: 6 CO₂ + 6 H₂O + light energy → C₆H₁₂O₆ (glucose) + 6 O₂
• Oxygen production supports aerobic respiration in living organisms
• Provides energy for plant growth and development
• Supports food chains and webs by producing glucose

Respiration

• Generates energy from glucose in cells
• Equation: C₆H₁₂O₆ (glucose) + 6 O₂ → 6 CO₂ + 6 H₂O + energy (ATP)
• Aerobic respiration occurs in presence of oxygen, anaerobic respiration in its absence
• Releases energy for cellular activities
• Vital for energy production in all living organisms

Nutrition

• Obtaining and utilizing nutrients for energy and growth
• Autotrophic nutrition: producing own food through photosynthesis
• Heterotrophic nutrition: obtaining food from other sources, e.g., ingestion
• Essential for growth, maintenance, and repair of cells and tissues
• Supports overall health and well-being

Transportation

• Movement of materials within an organism
• Passive transport: diffusion and osmosis
• Active transport: pumps and carrier proteins
• Delivers oxygen and nutrients to cells
• Removes waste products
• Maintains homeostasis

Excretion

• Removes waste products from the body
• Kidneys filter blood and excrete urine
• Lungs exhale carbon dioxide
• Skin removes waste through sweat
• Liver detoxifies and excretes bile
• Removes toxic substances
• Maintains chemical balance and homeostasis
• Supports overall health and well-being